In a time of increasing environmental change caused by anthropogenic disturbance,there is a greater need to understand animal adaptations to manmade environments.In this regard,the measurement of stress-related endocr...In a time of increasing environmental change caused by anthropogenic disturbance,there is a greater need to understand animal adaptations to manmade environments.In this regard,the measurement of stress-related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such space.The aims of the present study were to validate fecal glucocorticoid metabolite(fGCM)concentrations as a measure of stress using samples from a male African clawless otter(Aonyx capensis;n=1)and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South Africa.From the 5 different enzyme-immunoassays(EIA)tested,a cortisol and oxoetiocholanolone(measuring 11,17 dioxoandrostanes)EIA revealed the highest response(74%and 48%increase,respectively)30 and 24 hours after a stress event(translocation of a captive individual as part of its rehabilitation prior to release),respectively.For both EIAs,fGCM concentrations were comparable for samples collected up to 3 h post-defecation.Using the cortisol EIA for subsequent analyses,fGCM concentrations of animals from the transformed area(n=20;mean[±SD]:0.468[±0.539]µg/g dry weight[DW])were significantly higher(P=0.013)than those from otters in the natural areas(n=17;0.242[±0.226]µg/g DW).These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.展开更多
文摘In a time of increasing environmental change caused by anthropogenic disturbance,there is a greater need to understand animal adaptations to manmade environments.In this regard,the measurement of stress-related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such space.The aims of the present study were to validate fecal glucocorticoid metabolite(fGCM)concentrations as a measure of stress using samples from a male African clawless otter(Aonyx capensis;n=1)and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South Africa.From the 5 different enzyme-immunoassays(EIA)tested,a cortisol and oxoetiocholanolone(measuring 11,17 dioxoandrostanes)EIA revealed the highest response(74%and 48%increase,respectively)30 and 24 hours after a stress event(translocation of a captive individual as part of its rehabilitation prior to release),respectively.For both EIAs,fGCM concentrations were comparable for samples collected up to 3 h post-defecation.Using the cortisol EIA for subsequent analyses,fGCM concentrations of animals from the transformed area(n=20;mean[±SD]:0.468[±0.539]µg/g dry weight[DW])were significantly higher(P=0.013)than those from otters in the natural areas(n=17;0.242[±0.226]µg/g DW).These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.
